Before salmon managers begin to focus on harvest quotas and seasons for salmon fishing, they must work out predictions about the number of salmon coming back to each management area throughout the Northwest.
So how do the managers go about predicting this year’s salmon runs? It gets pretty technical, but it is basically a combination of counting the number of salmon smolts that leave selected streams and then calculating a rate of survival to determine the number of adults that will come back.
Numerous conditions affect whether eggs and fry will survive to smolt stage and make it out of a stream, just as many factors can cause the death of the young fish after they leave freshwater. I’m tempted to describe these factors here, but instead will defer to Mara Zimmerman, who heads the Wild Salmonid Production Evaluation Unit. Her well-written report on the “2011 Wild Coho Forecasts…” (PDF 376 kb) provides an excellent education into how coho are estimated. Check it out.
I was one of three newspaper reporters who attended Tuesday’s meeting in Olympia. It was easy to tell the difference between my handling of this story and the approaches by Jeffrey P. Mayor, who writes for the Olympian and the News Tribune in South Puget Sound, and Allen Thomas, who writes for the Columbian in Vancouver (Clark County).
The biggest difference is that those guys are sports or outdoor reporters, mainly interesting in telling their readers what fishing will be like this year. As an environmental reporter, my primary focus is to describe how the salmon are doing ecologically — although I do recognize that many readers of my stories are anglers who also want to know about fishing.